1. Field
This document relates to an organic light emitting display device and a method for manufacturing the same.
2. Related Art
An organic light emitting element used for an organic light emitting display device is a self-luminous element in which an emission layer is formed between two electrodes. The organic light emitting element is an element that emits light when electrons and holes are injected from an electron injection electrode (cathode) and a hole injection electrode (anode) to an emission layer and excitons created by recombination of the injected electrons and holes transition from an excited state to a base state.
In the organic light emitting display device, when a scan signal, a data signal, and electric power are supplied to a plurality of subpixels disposed in a matrix form, transistors, etc included in a selected subpixel are driven. Hereupon, an organic light emitting diode emits light in response to the current formed therein to display an image.
Some organic light emitting display devices are implemented as an organic light emitting display (hereinafter, referred to RGBW OLED) having a subpixel structure of red, green, blue, and white to increase light efficiency and prevent degradations in the luminance and chromaticity of pure colors.
The RGBW OLED implements RGBW by using a white organic light emitting diode for emitting white light and color filters for converting the white light into red light, green light, and blue light. In this structure, a white subpixel comprises no color filter because it emits white light as it is. Due to this, a white organic light emitting diode formation layer of the white subpixel is lower than those of red, green, and blue subpixels. Thus, the vertical distance between an underlying wire and a first electrode of the white organic light emitting diode is short. That is, the white subpixel has a smaller step difference than the other subpixels.
For this reason, when the pattern (e.g., insulating film, electrode, etc) of the conventional RGBW OLED is lost due to impurities (e.g., particles) introduced during a process, such as photolithography, etching, cleaning, etc, short-circuiting or overcurrent occurs between the underlying wire and the first electrode included in the white subpixel. Partial burning of the device due to such short-circuiting or overcurrent between different electrodes may spread across the entire panel, so a solution to this problem is required.